LED display device
First Claim
1. A light emitting diode for emitting spontaneous radiation and having a double heterostructure, comprising:
- a) an active layer for emitting the spontaneous radiation having a give wavelength;
b) a first clad layer of a first conductivity type formed on the active layer;
c) a first clad layer of a second conductivity type formed under the active layer;
d) a second clad layer of the first conductivity type formed on the first clad layer of the first conductivity type;
e) a reflection layer formed under the first clad layer of the second conductivity type for vertically reflecting the spontaneous radiation;
f) a current block layer formed on a part of the second clad layer;
g) a current diffusion layer formed on the current block layer and on an exposed surface of the second clad layer; and
h) an upper metal electrode locally formed above or on a part of the current diffusion layer so to define an optical aperture for emitting the spontaneous radiation upwardly,the forbidden band gap of the first clad layer of the first conductivity type being smaller than that of the second clad layer of the first conductivity type.
1 Assignment
0 Petitions
Accused Products
Abstract
A semiconductor light emitting device has a double heterostructure. The device is composed of an active layer and clad layers that sandwich the active layer. At least one of the clad layers has a multilayer structure having at least two element layers. The Al mole fraction of an element layer, which is proximal to the active layer, of the multilayer structure is smaller than that of the other element layer thereof distal from the active layer. This arrangement improves the crystal quality of an interface between the active layer and the clad layer of multilayer structure and effectively confines carriers in the active layer.
-
Citations
43 Claims
-
1. A light emitting diode for emitting spontaneous radiation and having a double heterostructure, comprising:
-
a) an active layer for emitting the spontaneous radiation having a give wavelength; b) a first clad layer of a first conductivity type formed on the active layer; c) a first clad layer of a second conductivity type formed under the active layer; d) a second clad layer of the first conductivity type formed on the first clad layer of the first conductivity type; e) a reflection layer formed under the first clad layer of the second conductivity type for vertically reflecting the spontaneous radiation; f) a current block layer formed on a part of the second clad layer; g) a current diffusion layer formed on the current block layer and on an exposed surface of the second clad layer; and h) an upper metal electrode locally formed above or on a part of the current diffusion layer so to define an optical aperture for emitting the spontaneous radiation upwardly, the forbidden band gap of the first clad layer of the first conductivity type being smaller than that of the second clad layer of the first conductivity type. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
-
-
27. A light emitting diode for emitting spontaneous radiation and having a double heterostructure, comprising:
-
a) an active layer for emitting the spontaneous radiation having a given wavelength; b) a first clad layer of a first conductivity type formed on the active layer; c) a first clad layer of a second conductivity type formed under the active layer; d) a second clad layer of the second conductivity type formed under the first clad layer of the second conductivity type; e) a reflection layer formed under the second clad layer for vertically reflecting the spontaneous radiation; f) a current block layer formed above or on the first clad layer of the first conductivity type; g) a current diffusion layer formed on the current block layer and above or on the first clad layer of the first conductivity type; and h) an upper metal electrode locally formed above or on a part of the current diffusion layer so to define an optical aperture for emitting the spontaneous radiation upwardly, the forbidden band gap of the first clad layer of the second conductivity type being smaller than that of the second clad layer of the second conductivity type. - View Dependent Claims (28, 29, 30, 31, 32, 33, 34, 35, 36)
-
-
37. A light emitting diode for emitting spontaneous radiation and having a double heterostructure, comprising:
-
a) an active layer for emitting the spontaneous radiation having a predetermined wavelength; b) a clad layer of a first conductivity type formed on the active layer; c) a clad layer of a second conductivity type formed under the active layer; d) a reflection layer formed under the clad layer of the second conductivity type for vertically reflecting the spontaneous radiation; e) a current block layer formed above or on the clad layer of the first conductivity type; f) a current diffusion layer formed on the current block layer and above or on the clad layer of the first conductivity type; and g) an upper metal electrode locally formed above or on a part of the current diffusion layer so to define an optical aperture for emitting the spontaneous radiation upwardly, the Al mole fraction of the active layer side of at least one of the clad layers being smaller than that of the other side, which is distal from the active layer, of the same clad layer. - View Dependent Claims (38, 39, 40, 41, 42, 43)
-
Specification